One thing though that would make it perfect is to make nodebb able to also handle comments on blog / news posts. Kind of like Disqus.
This is something that I would really like to see before I make the switch too.
But that's what pagination is for. And if after 5000 posts the subject of the original topic has not been resolved, then it will never be.
I have a tutorial on my blog with more than 550 comments. If I had a good forum platform with a good search feature, most of the comments would not have been asked.